1. Field of the Invention
The invention relates to a connector and to a method for mounting such a connector.
2. Detailed Description of the Related Art
A card edge connector is disclosed in Japanese Unexamined Patent Publication No. 56(SHO)-136480 and also is identified by the numeral 100 in FIGS. 22 and 23 herein. The card edge connector 100 is constructed to receive an end of a substrate 101. Terminals 102 in the form of a thin film are provided at the end of the substrate 101. The card edge connector 100 has upper and lower terminal fittings 104 for holding the terminals 102 from opposite sides along the thickness direction of the substrate 101. The terminal fittings 104 are formed with elastic contact pieces 103 that can elastically contact the terminals 102. A spacing L between the contact pieces 103 is less than thickness M of the substrate 101. Thus, the elastic contact pieces 103 hold the substrate 101 at a suitable contact pressure when the substrate 101 is mounted into the card edge connector 100.
The card edge connector 100 has several drawbacks. For example, corners 105 at the end of the substrate 101 may damage the contact pieces 103 while the substrate 101 is being mounted into the connector 100.
Further, the contact pressure between the elastic contact pieces 103 and the terminals 102 needs to be sufficiently high to stabilize contact resistance between the terminal fittings 104 and the terminals 102. This requires a large elastic deformation of the contact pieces 103 and a corresponding short spacing L. Circuits (not shown) in the card edge connector 100 may be shorted by the contact of the upper and lower elastic contact pieces 103 before the substrate 101 is mounted. Additionally, the elastic contact pieces 103 may be deformed.
In view of the above, an object of the invention is to provide a connector and a mounting method to hold a substrate and elastic contact pieces stably in contact with each other while avoiding a short circuit and a deformation of the contact pieces.
The invention is directed to a connector with a first housing surrounding one or more terminals on an outer end surface of a substrate, and a second housing connectable with the first housing. The second housing has one or more terminal fittings that can be brought into contact with the terminals on the substrate. Each terminal fitting comprises a contact piece that is elastically or resiliently deformable along a thickness direction of the substrate. Thus, the contact piece can be brought elastically or resiliently into contact with a corresponding terminal on the substrate. The first housing comprises at least one pressing portion for pressing the corresponding contact pieces toward the terminals on the substrate when the first and second housings are mated.
The terminals may be provided on only one of the opposite surfaces of the substrate. However, it is preferable to provide the terminals on both opposite surfaces of the substrate to follow the conventional construction of substrates and terminals and to shorten the width of the substrate.
The contact pieces preferably are provided to conform to the location of the terminals of the substrate. Thus, the contact pieces preferably elastically or resiliently contact and hold the substrate from its opposite sides, and contact pressure can be stabilized.
The pressing portions preferably contact the contact pieces directly and are inserted into pressing portion insertion spaces provided in the second housing at a side of the contact pieces opposite from the substrate. The contact pieces can deform elastically or resiliently in the pressing portion insertion spaces and in a direction away from the substrate. Thus, even if the substrate contacts the elastic contact pieces during connection of the two housings, the contact pieces can be deformed elastically or resiliently into the pressing portion insertion spaces. Therefore, the substrate is not likely to damage the contact pieces. Alternatively, second pressing portions may be provided in the second housing for pressing the contact pieces, and the first pressing portions may press the second pressing portions to press the contact pieces indirectly.
The contact pieces preferably are at retracted positions away from the outer surface of the substrate along the thickness direction before the two housings are connected with each other. The pressing portions move the contact pieces into the contact with the terminals after contact portions of the contact pieces pass the corner of the substrate during a connecting operation of the two housings. Thus, the contact pieces are not likely to be deformed by contact with a corner of the substrate when the two housings are being connected.
The contact portion of each contact piece preferably is closer to the front end of the second housing than the distal end of the contact piece is. Additionally, a base portion of the contact piece is more backward than the contact portion. Accordingly, the contact piece has a turned construction and the position where the corresponding pressing portion acts and the position of the contact portion can be proximate to each other along forward and backward direction. Thus, pressing forces from the pressing portions act substantially along the thickness direction of the substrate, and contact pressures acting between the substrate and the contact pieces can be stabilized more easily. Additionally, the distal ends of the contact pieces are not caught by the substrate even if the contact portions are pulled backward by the contact with the substrate during the connecting operation of the two housings.
The second housing preferably comprises one or more cavities for accommodating the respective terminal fittings. Engaging pieces extend into the respective cavities and elastically engage the terminal fittings when the terminal fittings are mounted in proper positions in the cavities. The contact portions preferably are spaced sufficiently from the engaging pieces to avoid contact with the engaging pieces while the terminal fittings are being mounted into the cavities.
The pressing portions preferably contact corresponding press receiving portions of the terminal fittings. The press receiving portions are arranged at an angle different from 0xc2x0 or 180xc2x0 with respect to a mating direction of the connector housings.
The second housing preferably is provided with one or more pressing portion insertion openings for inserting corresponding pressing portions into pressing portions insertion spaces in the second housing near the resilient contact pieces. The resilient contact pieces preferably can be deflected into the corresponding pressing portions insertion space in case of an interaction with the substrate.
The invention also is directed to a method of connecting a connector. The connector has a first housing surrounding one or more terminals on outer end surfaces of a substrate, and a second housing connectable with the first housing and provided with one or more terminal fittings that can be brought into contact with the terminals of the substrate. The method comprises providing a contact piece on each terminal fitting which is resiliently deformable towards or away from the substrate. The method also comprises providing one or more pressing portions on the first housing and pressing by means of the pressing portions the corresponding resilient contact pieces substantially toward the terminal portions when the first and second housings are fitted to each other. Thus, the resilient contact pieces of the terminal fittings are brought resiliently into contact with the corresponding terminal portions of the substrate.
The pressing portions preferably press the resilient contact pieces substantially toward the substrate after contact portions of the resilient contact pieces pass a corner of the substrate during a connecting operation of the two housings.
These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments.